Dental-matrix holder.



No. 648,l96. Patented Apr. 24, I900. w. P. DICKINSON.

DENTAL MATRIX HOLDER. (Application w 7511.24, 1900.)

(No Model.)

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UNITED STATES PATENT tries.

l/VILLIAM P. DICKINSON, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO' JAMES W.IVORY, OF PHILADELPHIA, PENNSYLVANIA.

DENTAL-MATRIX HOLDER.

SPECIFICATION forming part of Letters Patent N 0. 648,196, dated April24, 1900. Application filed January 24, 1900. Serial No. 2,572. (Nomodel.)

To aZZ whom it may concern.-

Be it known that LWILLIAM P. DICKINSON, a citizen of the United States,residing atMinneapolis, in the county of Hennepin, State of Minnesota,have. invented a new and use ful Improvement in Dental-Matrix Holders,which improvement is fully set forth in the following specification andaccompanying drawings.

My invention consists of a holder for a dental matrix formed ofwedge-shaped jaws or points, carriers therefor, and means for forcingsaid jaws toward each other, whereby they bear against the matrix andretain the same firmly in position, and a compound joint whereby saidjaws are adapted to conform Vertically and horizontally to anyconstruction or irregularities in the form of teeth.

Figure 1 represents a perspective view of a dental-matrix holderembodying my invention. Fig. 2 represents an end elevation Fig. 3represents a section thereof on line so 00, Fig. 1.

Similar letters of reference indicate corresponding parts inthe figures.

Referring to the drawings, A designates a pair of arms or levers, whichare connected at one end by the pivot 13 and provided at the other endwith the wedge shaped jaws or points 0, the latter having journals D,which are mounted in the bosses or bearing-pieces E, the latter beingswiveled on said arms A, it being noticed that the bearing-pieces arerotatable on the arms A and the jaws are rotatable in said pieces,forming a compound joint the members of which are independent of eachother in planes at or about at a right angle to each other, the journalsD being horizontaLor approximately so, and the pieces E vertical, orapproximately so.

F designates a yoke which is formed with slots G, through which freelypass the arms A, one end of said yoke having fitted to it the screw H,which is adapted to bear against the adjacent arm A, while the oppositeclosed end J of the yoke is adapted to bear against the other arm, itbeing evident that by prop erly rotating said screw H said arms may bedrawn together and the jaws O thereby caused to approach each other.

K designates the matrix, which is adapted to be placed by the side of acavity in a tooth to be filled and requires to be firmly held inposition.

When the matrix is located, the jaws bear against the back or outer faceof the same, after which the screw H is rotated, whereby the arms A aredrawn together and the jaws moved toward each other, so as to press thematrix against the tooth and hold the same firmly in position. Owing toany inequalities in the outer face of the tooth, or from other causes,the jaws mayturn on the bosses E and the latter may turn on the arms A,whereby the matrix is made to conform to the contour of the tooth and isfirmly retained in position, and the operation of filling may beconveniently and reliably performed. NVhen the screw is properly rotatedin the reverse directions, the arms separate, due to the action of thespring L employed, and the jaws open, whereby they leave the matrix, andthe latter may be removed.

Having thus described myinvention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a dental-matrix holder, an arm, a point and a compound jointconnecting said point with said arm, whereby said point is adapted toaccommodate itself to the matrix in both vertical and horizontaldirections.

2. A dental matrix having a point, a carrying-arm therefor and anintermediate joint consisting of a boss, a journal thereon mounted onsaid arm, and a journal on said point mounted on said boss, said journalbeing at or about a right angle to each other.

' WILLIAM P. DICKINSON.

Witnesses:

E. F. HERTZ, W. H. LANDIS.

